Electronic apparatus, wireless communication method and computer-readable medium

ABSTRACT

The present disclosure relates to an electronic apparatus, a wireless communication method and a computer-readable medium. The electronic apparatus for wireless communication according to one embodiment comprises a processing circuit. The processing circuit is configured to perform control to send or receive configuration information. The configuration information is related to configuration of a reference signal used in a discovery process of an integrated access backhaul (IAB) link node.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. application Ser. No.17/256,655, filed Dec. 29, 2020, which is based on PCT filingPCT/CN2019/098956, filed Aug. 2, 2019, which claims priority from CN201810909745.8, filed Aug. 10, 2018, the entire contents of each areincorporated herein by reference.

FIELD

The present disclosure relates generally to the field of wirelesscommunication, and more particularly to an electronic device, a wirelesscommunication method and a computer readable medium related to anIntegrated Access and Backhaul link (IAB).

BACKGROUND

In order to implement a flexible deployment of 5G NR(New Radio) basestations, research on IAB technology has been proceeded. First, theresearch relates to a relay node with fixed position. As shown in FIG.16 , IAB node A establishes a connection with a core network by a cable,and this node is referred to as an IAB donor node. IAB nodes B and Cestablish a connection with an IAB donor in a wireless backhaul (BH)manner, and then establish a connection with the core network. The nodesB and C are referred to as IAB nodes.

A periodic discovery is needed for TAB nodes that access the network todetect a surrounding candidate IAB node, as shown in FIGS. 17 and 18 .The discovery process facilitates finding a suitable candidate toestablish multiple BH connections or backup connections to provide therequired robustness.

SUMMARY

Brief summary of the present disclosure is given hereinafter, so as toprovide basic understanding in some aspects of the present disclosure.However, it should be understood that this summary is not an exhaustiveoverview of the present disclosure. It is neither intended to determinekey part or critical part of the present disclosure, nor intended todefine the scope of the present disclosure. An object of the summary isonly to give some concepts in a simplified manner, which serves as apreface of a more detailed description described later.

According to an embodiment, an electronic device for wirelesscommunication includes a processing circuitry. The processing circuitryis configured to: preform control to transmit or receive configurationinformation related to configuration of a reference signal for adiscovery process of an Integrated Access and Backhaul link node.

According to another embodiment, a wireless communication methodincludes: transmitting or receiving configuration information related toconfiguration of a reference signal for a discovery process of anIntegrated Access and Backhaul link node.

According to yet another embodiment, an electronic device for wirelesscommunication includes a processing circuitry. The processing circuitryis configured to: acquire hop count information indicating a relay hopcount of a relay node from a donor node. The donor node is an IntegratedAccess and Backhaul link node which is in wired connection with a corenetwork, and the relay node is a node which is not in wired connectionwith the core network.

According to still another embodiment, a wireless communication methodincludes: acquiring hop count information indicating a relay hop countof a relay node from a donor node. The donor node is an IntegratedAccess and Backhaul link node which is in wired connection with a corenetwork, and the relay node is a node which is not in wired connectionwith the core network.

According to yet another embodiment, an electronic device for wirelesscommunication includes a processing circuitry. The processing circuitryis configured to: determine, based on a time offset between signals ofdifferent nodes connected via a backhaul link, an adjustment ofsynchronization time for at least one node of the different nodes.

According to still another embodiment, a wireless communication methodincludes: determining, based on a time offset between signals ofdifferent nodes connected via a backhaul link, an adjustment ofsynchronization time for at least one node of the different nodes.

According to an embodiment of the present disclosure, a computerreadable medium is further provided. The computer readable mediumincludes executable instructions that, when executed by an informationprocessing apparatus, cause the information processing apparatus toimplement the method according to the above embodiments.

According to the embodiments of the present disclosure, a discoverybetween IAB nodes can be effectively implemented.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be understood better with reference to thedescription given in conjunction with the drawings in the following. Thesame or similar component is indicated by the same or similar referencenumeral throughout all the drawings. The drawings together with thedetailed description below are incorporated in the present specificationand form a part of the present specification, and are used to furtherillustrate preferable embodiments of the present disclosure and explainthe principle and advantages of the present disclosure. In the drawings:

FIG. 1 is a block diagram showing a configuration example of anelectronic device for wireless communication according to an embodimentof the present disclosure;

FIG. 2 is a block diagram showing a configuration example of anelectronic device for wireless communication according to anotherembodiment of the present disclosure;

FIG. 3 is a block diagram showing a configuration example of anelectronic device for wireless communication according to anotherembodiment of the present disclosure;

FIG. 4 is a block diagram showing a configuration example of anelectronic device for wireless communication according to still anotherembodiment of the present disclosure;

FIG. 5 is a block diagram showing a configuration example of anelectronic device for wireless communication according to anotherembodiment of the present disclosure;

FIG. 6 is a flowchart showing a procedure example of a wirelesscommunication method according to an embodiment of the presentdisclosure;

FIG. 7 is a block diagram showing a configuration example of anelectronic device for wireless communication according to an embodimentof the present disclosure;

FIG. 8 is a block diagram showing a configuration example of anelectronic device for wireless communication according to anotherembodiment;

FIG. 9 is a flowchart showing a procedure example of a wirelesscommunication method according to an embodiment of the presentdisclosure;

FIG. 10 is a block diagram showing a configuration example of anelectronic device for wireless communication according to an embodimentof the present disclosure;

FIG. 11 is a block diagram showing a configuration example of anelectronic device for wireless communication according to anotherembodiment of the present disclosure;

FIG. 12 is a flowchart showing a procedure example of a wirelesscommunication method according to an embodiment of the presentdisclosure;

FIG. 13 is a block diagram showing an exemplary structure of a computerthat implements a method and an apparatus according to the presentdisclosure;

FIG. 14 is a block diagram showing an example of a schematicconfiguration of a smartphone to which the technology according to thepresent disclosure may be applied;

FIG. 15 is a block diagram showing an example of a schematicconfiguration of a gNB (a base station in a 5G system) to which thetechnology according to the present disclosure may be applied;

FIG. 16 is a schematic diagram illustrating an IAB network scenario;

FIG. 17 and FIG. 18 are schematic diagram illustrating an IAB nodediscovering scenario;

FIG. 19A, FIG. 19B and FIG. 19C show an example of a configuration of asynchronization signal block (SSB);

FIG. 20 shows an exemplary process of evaluating an access performanceof a user equipment (UE);

FIG. 21 shows an example of an IAB scenario;

FIG. 22 shows an exemplary process of a configuration of a channel stateinformation reference signal (CSI-RS);

FIG. 23 shows an example of an IAB scenario;

FIG. 24 shows an exemplary process of a configuration of a CSI-RS;

FIG. 25 shows an example of an IAB scenario;

FIG. 26 shows an exemplary process of a configuration of a CSI-RS;

FIG. 27 shows an example of an IAB scenario;

FIG. 28 shows an exemplary process of a configuration of a CSI-RS;

FIG. 29 shows an example of an IAB scenario;

FIG. 30 shows an exemplary process of a configuration of a CSI-RS;

FIG. 31 is a schematic diagram illustrating a case in which transmissionand reception for SSBs conflict between IAB nodes;

FIG. 32 is a schematic diagram illustrating a case of interferencesbetween SSBs of IAB nodes;

FIG. 33 shows an example of an IAB network deployment;

FIG. 34 to FIG. 39 show an example of an arrangement of a SSB for abackhaul link;

FIG. 40 shows an example of an adjustment of a SSB for a backhaul link;

FIG. 41 shows an example of an IAB scenario;

FIG. 42 shows an exemplary process of a configuration of a SSB;

FIG. 43 shows an example of an IAB scenario;

FIG. 44 shows an exemplary process of a configuration of a SSB;

FIG. 45 shows an example of an IAB scenario;

FIG. 46 shows an exemplary process of a configuration of a SSB;

FIG. 47 shows an example of an IAB scenario;

FIG. 48 shows an exemplary process of a configuration of SSB muting;

FIG. 49 shows another exemplary process of a configuration of SSBmuting;

FIG. 50 shows yet another exemplary process of a configuration of SSBmuting;

FIG. 51A and FIG. 51B are schematic diagrams illustrating aninterference between IAB nodes;

FIG. 52 to FIG. 54 show an exemplary process of a coordination betweenIAB nodes;

FIG. 55 is a schematic diagram illustrating a scenario of an IAB linkreselection;

FIG. 56 shows an example of a correspondence between a hop count andreference signal resource;

FIG. 57 and FIG. 58 show process examples of a link reselection;

FIG. 59 and FIG. 60 show process examples of performing a linkreselection based on multiple candidate links;

FIG. 61 and FIG. 62 show process examples of a link reselection assistedby a donor node;

FIG. 63 and FIG. 64 are schematic diagrams illustrating a scenario of asynchronization measurement for a node;

FIG. 65 is a schematic diagram illustrating a configuration example of atiming maintenance signal; and

FIG. 66 shows an exemplary process of performing node synchronizationusing a timing maintenance signal.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure will be described below withreference to the drawings. Elements and features described in one of thedrawings or one embodiment of the present disclosure may be combinedwith elements and features described in one or more other drawings orembodiments. It should be noted that representations and descriptions ofcomponents and processing which are irrelevant to the present disclosureand known by those skilled in the art are omitted in the drawings andthe specification for clarity.

As shown in FIG. 1 , an electronic device 100 for wireless communicationaccording to the present embodiment includes a processing circuitry 110.The processing circuitry 110 may be implemented, for example, by aspecific chip, a chipset, a central processing unit (CPU), or the like.

The processing circuitry 110 includes a control unit 111. It should benoted that, although the control unit 111 and the like are shown in aform of functional blocks in the drawings, it should be understood thatfunctions of the respective units may be implemented as a whole by theprocessing circuitry, and it is not necessary to be implemented bydiscrete actual components in the processing circuitry. In addition,although the processing circuitry is shown by a block in the drawings,the electronic device may include multiple processing circuitry, andfunctions of the respective units may be distributed to the multipleprocessing circuitry, thereby cooperatively operating by the multipleprocessing circuitry to perform these functions.

The control unit 111 is configured to preform control to transmit orreceive configuration information related to configuration of areference signal for a discovery process of an Integrated Access andBackhaul link (IAB) node.

As described above, the electronic device according to an embodiment ofthe present disclosure is configured to discover an IAB node. In orderto deploy cellular cells more flexibly and densely, IAB is introduced toimplement wireless connections between base stations. In the network,some base stations (IAB donor nodes) are connected with a core networkby means of, for example, optical fiber cables, and the rest of deployedaccess points (small base stations or relay devices) (which may bereferred to as IAB relay nodes or IAB nodes herein) are connected withIAB donor nodes via wireless links in a single-hop manner and amulti-hop manner. IAB nodes connected to the network need toperiodically discover surrounding candidate backhaul links (BH). In acase of multi-hop connections, among two adjacent nodes on the link, anode that is closer to the donor node may be referred to as an superiornode or a parent node, and a node that is farther away from the donornode may be referred to as a subordinate node or a child node.

The electronic device according to the present embodiment may beimplemented on the side of an IAB donor node or an IAB relay node. In acase of being implemented on the donor node side, the electronic devicemay, for example, transmit configuration information to a subordinatenode. In a case of being implemented on the side of the relay node, theelectronic device may receive configuration information from the donornode or may transmit the configuration information to a subordinatenode.

Furthermore, in a case that configuration information is further relatedto an access link (AC) between a user equipment (UE) and an access point(IAB node), the electronic device may also be implemented at the UEside, and may, for example, receive configuration information from theaccess point.

As an example, a synchronization signal block (SSB) or a channel stateinformation reference signal (CSI-RS) may be used as a reference signalfor a discovery process of an IAB node.

According to an embodiment, the configuration information includes amultiplexing manner of a SSB for an access link and a SSB for a backhaullink.

A SSB signal for cell access by the UE is configured in a unit of onehalf-frame. The base station broadcasts periodically, and configures ameasurement period and a measurement duration for the UE by systeminformation blocks SIB2 and SIB4, or may perform configuration byspecial signaling. In order not to produce interference to an access ofthe UE, the SSB for the access link (AC SSB) and the SSB for thebackhaul link (BH SSB) are orthogonal in time.

According to an exemplary manner, a part of SSB resource positions in aperiod of the SSB for the access link may be allocated to the SSB forthe backhaul link.

As shown in FIG. 19A, in a SSB signal configured in a unit of onehalf-frame (5 ms), a part of the SSB resource positions (for example,the last two positions) may be allocated to the BH SSB.

According to another exemplary manner, a period of the SSB for theaccess link may be increased, and a SSB for the backhaul link may bearranged in an increased part of the period.

As shown in FIG. 19B, a period in a unit of one half-frame (5 ms) isextended to a period in a unit of two half-frames (10 ms), and SSBresource positions in the added one half-frame is allocated to the BHSSB. It should be noted that all the SSB resource positions in theincreased part of the period may be not allocated to the BH SSB, andsome SSB resource positions may be allocated to the AC SSB.

Furthermore, a combination of the above methods may also be adopted,that is, when a part of SSB resource positions in an original period ofthe AC SSB is allocated to the BH SSB, a period of the AC SSB isincreased and a BH SSB is arranged in an increased part of the period,as shown in FIG. 19C.

The present disclosure is not limited to specific configuration, such asthe number and position and the like of AC SSB and BH SSB, in the aboveexample.

Furthermore, in order to reduce an impact on an access of the UE, anaccess quality supervision mechanism for a UE may be introduced. Afteran AC SSB and a BH SSB are configured, access performances andsynchronization performances of the UE may be periodically detected, andan adjusted is performed correspondingly in a case of a degradation ofaccess performances.

According to an embodiment, a multiplexing manner of an AC SSB and a BHSSB may be adjusted based on an access performance of a user equipment.For example, in a case of a degradation of access performances, a SSBfor an access link may be increased.

For example, the adjustment may be triggered in a case that an accesslatency of the user equipment exceeds a predetermined threshold.

More specifically, an access latency threshold may be introduced. In acase that the access latency of the UE is greater than the threshold dueto a reduction of the AC SSB, the UE may request an AC SSB to an IABnode. The threshold may be preconfigured, or may be obtained from a SSBsignal. In response to the request of the UE, the IAB node may adjust aposition of the AC SSB, as shown in FIG. 20 .

For example, the access latency threshold may be indicated by addingfield information in the SSB signal, as shown in Table 1-1 below.

TABLE 1-1 Field Value and description AC latency threshold Bit string,latency threshold of UE

The adjustment of UE accessing and monitoring SSB resources may followthe existing SSB monitoring configuration, including a duration (thenumber of sub-frame that is monitored) and a monitoring period (5 ms, 10ms, 20 ms, 40 ms, 80 ms . . . ).

Furthermore, an adjustment of the AC SSB may include, for example,configuring an additional AC SSB position for the UE by specialsignaling or reducing a period of monitoring a SSB for the UE.Alternatively, BH SSB positions within a half-frame may be reduced or aBH SSB period may be increased for an AC SSB.

Furthermore, for a UE that has not accessed the network, since the UEdoes not know a position of an AC SSB of a cell before accessing thecell, it is possible to detect the BH SSB.

In order to enable the UE to determine whether the received SSB is an ACSSB or a BH SSB, a power level may be used to distinguish the AC SSBfrom the BH SSB. For example, in a case that the received SSB is withina certain range, it is considered that the received SSB is an AC SSB.Alternatively, some SSB positions may be specifically reserved for theAC SSB of the UE (which has no access to the network).

Correspondingly, according to an embodiment, different power levels maybe applied to the SSB for the access link and the SSB for the backhaullink, or a specific SSB resource position may be set as a SSB for theaccess link.

An exemplary embodiment in which a SSB is used as a reference signal fora discovery process of an IAB node is described above. As describedabove, a CSI-RS may also be used as a reference signal for a discoveryprocess of an IAB node. CSI-RS transmission may be individuallyconfigured for some connections without direct impact on otherconnections or measurements. Furthermore, the CSI-RS transmission may beconfigured for a beam that is narrower than a beam of the SSB, andtherefore, it is possible to provide a possibility of beam evaluationfor a candidate BH link, which is beneficial for fast switching to aconnection of the candidate link.

Correspondingly, the reference signal for the discovery process of theIAB node may include a CSI-RS, and configuration information related tothe reference signal may include a multiplexing manner of a CSI-RS foran access link (AC CSI-RS) and a CSI-RS for a backhaul link (BH CSI-RS).

According to an embodiment, the CSI-RS for the backhaul link may betransmitted using a directional beam, and time-frequency resources ofthe CSI-RS for the access link and the CSI-RS for the backhaul link maybe multiplexed.

More specifically, the donor node may configure parameter information ofa directional beam for the relay node based on physical positioninformation of the relay node and a connection relationship among therelay nodes. For example, the donor node may obtain the physicalposition information or connection state of the relay node from a corenetwork. In addition, the physical position information of the relaynode and the connection relationship among the relay nodes may also bereported by the relay node to the donor node.

The donor node may configure parameter information of a directional beamof the BH SCI-RS for the relay node. The parameters may include, forexample, time-frequency resources, transmission directions of thedirectional beams, and time-frequency resources of the monitoreddirectional beam and the like.

The time-frequency resources configured by the donor node may bescheduled periodically, non-periodically or semi-statically. FIG. 22shows a signaling flow for a configuration in an exemplary scenarioshown in FIG. 21 . In FIG. 22 , hop1 represents a relay node with a hopcount of 1, that is, a child node of the donor node; hop2 represents arelay node with a hop count of 2, that is, a child node of the hop1node; and hop3 represents a relay node with a hop count of 3, that is achild node of hop2 node. As shown in FIG. 22 , the donor node transmitsCSI-RS transmission and reception configurations of the hop1 node, thehop2 node and the hop3 node to the hop1 node, the hop1 node transmitsCSI-RS transmission and reception configurations of the hop2 node andthe hop3 node to the hop2 node, and the hop2 node transmits CSI-RStransmission and reception configuration of the hop3 node to the hop3node.

The fields newly added in the CSI-RS transmission and receptionconfiguration provided by the donor node (as shown in Table 1-2 below)may include configurations of all child nodes, and each of the childnodes obtains configuration thereof.

TABLE 1-2 Field Value and description BH CSI-RS beam direction Bitstring (child node) BH CSI-RS resource type {non-periodic, semi-static,periodic} (child node) BH CSI-RS-ResourceSetList Bit string, resourcesfor transmitting (child node) a CSI-RS BH CSI-measConfig Unit, resourcesfor monitoring a (child node) CSI-RS by a IAB node

Furthermore, the donor node may configure parameter information ofdirectional beams for the relay node and a candidate node around therelay node based on direction information related to the candidate nodewhich is detected and reported by the relay node.

FIG. 23 shows an exemplary scenario, where a hop1 IAB node 1 representsa relay node with a hop count of 1, a hop1 IAB node 2 represents anotherrelay node with a hop count of 1, and a hop2 IAB node represents a relaynode with a hop count of 2, that is, a child node of the hop1 IAB node1.

The IAB node monitors a surrounding candidate IAB node based on a SSBsignal, and reports to the donor node, as shown in FIG. 24 . On the onehand, the donor node indicates resources for receiving and transmittinga CSI-RS to the IAB node 1, and on the other hand, the donor nodeindicates resources for receiving and transmitting a CSI-RS to the IABnode 2.

The configured time-frequency resources may be scheduled periodically,non-periodically or semi-statically.

As an example, the fields that may be added to the CSI-RS receptionconfiguration are shown in Table 1-3 below.

TABLE 1-3 Field Value and description BH CSI-RS resource type{non-periodic, semi-static, periodic} (child node) BH CSI-measConfig Bitstring, resources for monitoring a (child node) CSI-RS by a IAB node BHCSI-RS TX sresource Bit string, direction and time-frequency resourcesfor transmitting a CSI-RS by a IAB node

In addition, the donor node may also indicate, to the correspondingrelay node, time-frequency resources and direction information fortransmitting a CSI-RS.

In addition, the relay node may configure parameter information of adirectional beam based on direction information related to a surroundingcandidate node which is detected by the relay node and report theconfigured parameter information to the donor node.

For example, the IAB node may monitor the surrounding candidate IAB nodebased on the SSB signal, configure a direction of the CSI-RS based on adirection of the SSB signal, and configure a transmission direction andtime-frequency resources of directional beams of the CSI-RS based onremaining time resources of the CSI-RS, and report the time-frequencyresources of the directional beams of the CSI-RS to the donor node. Thedonor node may review and adjust, and configure positions of thetime-frequency resources for CSI-RS reception. Then, the IAB node maytransmit the CSI-RS on the configured resources. The exemplary scenarioand process are shown in FIG. 25 and FIG. 26 .

For example, the fields newly added in a CSI-RS configuration report areshown in Table 1-4 below.

TABLE 1-4 Field Value and description BH CSI-RS-ResourceSetList Bitstring, resources for (child node) transmitting a CSI-RS

An exemplary manner in which a CSI-RS is transmitted using a directionalbeam is described above. Furthermore, according to an embodiment, aCSI-RS for a backhaul link may be transmitted in a omnidirectional mode,and orthogonal time-frequency resources are used for the CSI-RS for theaccess link and the CSI-RS for the backhaul link.

For example, a part of CSI-RS resources may be fixed to be dedicated toan AC CSI-RS, and the remaining CSI-RS resources may be allocated basedon a link quality of the UE. An available AC CSI-RS reception group maybe broadcast through broadcast information, or may be indicated to theUE through special high level signaling. Similarly, the allocated BHCSI-RS reception group may be configured for child nodes throughbroadcast information, and may be also indicated to the IAB node throughspecial high level signaling. Two CSI-RS configuration manners, that is,a centralized configuration manner and a distributed configurationmanner, may be used.

Correspondingly, according to an embodiment, the donor node configuresthe CSI-RS time-frequency resources for the relay node based on physicalposition information of the relay node and a connection relationshipamong the relay nodes.

More specifically, the donor node may configure time resources forCSI-RS reception and transmission for the relay node based on geographiclocation information and a connection relationship for each relay node.An exemplary scenario and process are shown in FIG. 27 and FIG. 28 .First, the donor node configures CSI-RS RX resources for hop1 IAB nodes,and then configures the remaining BH CSI-RS time resources for the hop1IAB nodes. First, the donor node configures hop1 IAB nodes with aconnection relationship and a neighbor relationship to ensure that theCSI-RSs for the hop1 IAB nodes are orthogonal in time. The configurationmay include BH CSI-RS transmission and BH CSI-RS reception (monitoringthe IAB nodes of the same hop). Then, the donor node configures CSI-RStransmission time resources for an independent hop1 IAB node (the CSI-RSresources of any hop1 IAB node may be multiplexed). Then, based on thehop1 IAB node to which a hop2 IAB node is connected, the donor nodeconfigures CSI-RS reception time resources for the hop2 IAB node. Then,it configures CSI-RS transmission resources for the hop2 IAB nodesconnected to each other, to ensure that the time resources areorthogonal, and also configures CSI-RS reception resources. Then, thedonor node configures CSI-RS transmission resources for an independenthop2 IAB node. And so on, until all relay nodes are configured. Theabove process is repeated until all the relay nodes are configured.

The fields added in the CSI-RS transmission and reception configurationmay be shown in Table 1-5 below.

TABLE 1-5 Field Value and description BH CSI-RS resource type{non-periodic, semi-static, periodic} (child node) BHCSI-RS-ResourceSetList Bit string, resources for transmitting (childnode) a CSI-RS BH CSI-measConfig Bit string, Resources for monitoring(child node) a CSI-RS by a IAB node

The centralized manner is described above. On the other hand, the relaynode may configure time-frequency resources for a subordinate node ofthe relay node, and reports the configured time-frequency resources tothe donor node.

More specially, a parent node may configure CSI-RS reception timeresources (for monitoring the parent node and other IAB nodes) andCSI-RS transmission time resources for its child node. Then, the childnode configures CSI-RS transmission and reception resources for its ownchild nodes, to ensure that the CSI-RS time resources of those childnodes are orthogonal, and report to its parent node. It is assumed thatall the parent nodes save all the CSI-RS configuration information oftheir child nodes and perform adjustment in a case that the parent nodesdetect a CSI-RS detection conflict. An exemplary scenario and processare shown in FIG. 29 and FIG. 30 .

The fields added in the CSI-RS transmission and reception configurationmay be shown in Table 1-6 below.

TABLE 1-6 Field Value and description BH CSI-RS resource type{non-periodic, semi-static, periodic} BH CSI-RS-ResourceSetList Bitstring, resources for transmitting a CSI-RS BH CSI-measConfig Bitstring, Resources for monitoring a CSI-RS by a IAB node

According to the above-described embodiments, it is possible to providea BH SSB/CSI-RS resource configuration manner while ensuring accessperformances of a UE.

Furthermore, due to a limitation of half-duplex, an IAB node may notsimultaneously transmit a SSB signal and receive a SSB signal in a timeslot. As shown in FIG. 31 , if two adjacent IAB nodes (RN1 and RN2)transmit a SSB and receive a SSB in the same time, the RN1 and the RN2may not monitor SSB signals from each other. Furthermore, as shown inFIG. 32 , if the RN1 and the RN2 transmit SSB signals simultaneously, aRN3 may not accurately determine whether the SSB signal comes from RN1or RN2.

In order to ensure that all IAB nodes may periodically monitor thesurrounding candidate IAB nodes for potential usage, first, timeresources for transmitting a SSB by an IAB node and time resources fortransmitting a SSB by an adjacent node should be orthogonal, and the IABnode configures a SSB reception group, so that it may periodicallymonitor as many surrounding candidate nodes as possible.

Correspondingly, according to an embodiment, configuration informationrelated to the reference signal may include a multiplexing manner oftransmission and/or reception for the SSB.

The multiplexing manner may include time resources for transmission ofSSBs of adjacent nodes being orthogonal.

For example, the above multiplexing manner may be determined in thefollowing manner: configuring, by the donor node, time resources fortransmission of the SSB of the relay node based on physical positioninformation of the relay node and a connection relationship among therelay nodes; configuring, by the relay node, the time resources for asubordinate node of the relay node, and reporting, by the relay node,the configured time resources to the donor node; or detecting, by therelay node, a SSB transmitted by a surrounding node based on a hop countof the relay node, configuring, by the relay node, the time resourcesfor itself based on a detection result, and reporting, by the relaynode, the configured time resources to the donor node.

Hereinafter, the above three manners will be described with reference tospecific examples.

First, an exemplary manner of the donor node performing centralizedcontrol on SSB configuration is illustrated. FIG. 33 shows an example ofan IAB network deployment. FIG. 34 shows positions for transmission ofSSB for a donor node DN. FIG. 35 shows positions for reception andtransmission of a BH SSB for RN1-1. FIG. 36 shows positions forreception and transmission of a BH SSB for RN1-2. FIG. 37 showspositions for reception and transmission of a BH SSB for RN1-3. FIG. 38shows positions for reception and transmission of a BH SSB for RN1-1 andchild nodes. FIG. 39 shows positions for reception and transmission of aBH SSB for RN1-2 and child nodes. FIG. 40 shows a case in whichpositions for SSBs for RN2-2 and RN2-3 conflict.

The donor node may obtain, from a core network, geographic locationinformation and interconnection information related to all the connectedIAB nodes, including a hop count of an IAB node and a state of itsconnected IAB node(s). Resources positions for transmission andreception of SSBs for a backhaul link are centrally configured for theIAB nodes.

In a case that AC SSB positions and BH SSB positions have been allocatedaccording to the above embodiment, the donor node may allocate BH SSBsto all the IAB nodes of the hop1. According to a multiplexing mode ofSSBs, for example, in a case that there are an AC SSB and a BH SSB ineach half-frame, a BH SSB position for the donor node may be fixed. Asshown in FIG. 34 , a first position of each half-frame is configured asa BH SSB.

Then, the donor node may configure the hop1 IAB nodes. First, hop1 IABnodes with a connection relationship (such as RN1-1 and RN1-2 in FIG. 33) are configured, and orthogonal resources are configured for them. Asshown in FIG. 35 , in second, SSB TX positions of different half-frames,TX/RX positions of RN1-1 and RN1-2 may not be orthogonal, while RN1-1and RN1-2 and RN1-3 may not monitor with each other, so that RN1-1 andRN1-2 may multiplexes resources of RN1-3 for SSB TX, alternatively,RN1-3 may multiplex BH SSB TXs of RN1-1 and RN1-2. RN1-1, RN1-2 andRN1-3 may select some of the DN BH SSB positions (for example, positionsas indicated in FIG. 24 ) for monitoring.

RN1-1 may configure its child nodes (RN2-1 and RN2-2) based on itsremaining SSB. RN1-2 may configure its child nodes (RN2-3 and RN2-4)based on its remaining SSB positions. It is possible that RN2-2 andRN2-3 are configured with the same resources (as shown in FIG. 38 andFIG. 39 ). DN1 centrally coordinates SSB positions of RN2-2 and RN2-3during the configuration process, to avoid a conflict of transmissionand reception (as shown in FIG. 40 ).

An exemplary scenario and a process of the above configuration mannerare shown in FIG. 41 and FIG. 42 .

The fields added in a SSB transmission and reception configuration maybe shown in Table 2-1 below.

TABLE 2-1 Field Value and description BH SSB-MTC- BIT STRING, amonitoring period and periodicityAndOffset an offset value of a SSBsignal (including child nodes) (each in a unit of a sub-frame) BHSSB-MTC-duration Bit string, a duration of a measurement time window (ina unit of the number of sub-frames) BH SSB-TX-period Bit string, atransmission period of a SSB signal BH SSB-TX-resource Bit string, asub-frame position for transmission of a SSB signal

Next, an exemplary manner of configuring BH SSBs of IAB nodes in astepwise manner is illustrated.

In this way, the BH SSB TX position of the donor node remains unchangedand the period is adjustable. In a case that the period is increased,other idle positions may be allocated to an AC SSB for a UE. The donornode configures a SSB TX/RX position for its child nodes, and a childnode configures, based on its BH SSB TX/RX position, a BH SSB TX/RX forthe next level node.

Nodes of each level of informs a configuration result to a parent nodethereof. If finding a conflict, the parent node will adjust the SSB TX.

In addition, for nodes of each level, a time window may be configured tomonitor all surrounding candidate IAB nodes. In a case that SSBpositions conflict, the SSB TX may be adjusted by the node itself.

An exemplary scenario and a process of the above configuration mannerare shown in FIG. 43 and FIG. 44 .

The fields added in the SSB TX/RX configuration may be the same as thoseshown in Table 2-1.

Next, an exemplary manner of configuration of BH SSB TX/RX by IAB nodesthemselves in a distributed manner is illustrated.

An IAB node may determine a BH SSB position which it may use in ahalf-frame, based on a hop count where the IAB node is located. If thehop count is greater than the number of BH SSBs in a half-frame, a fixedSSB position in a half-frame may be occupied. Specifically, SSB signaldetection may be performed first. If no SSB signal is configured at thisposition, the position may be configured as SSB TX, and some SSB signalsmay be selected for monitoring. After the BH SSB is configured, theremaining SSB positions may be allocated to AC SSB for a UE. The IABnode may report the configuration manner to the donor node. If there isa conflict, the donor node may perform adjustment.

An exemplary scenario and a process of the above configuration mannerare shown in FIG. 45 and FIG. 46 .

The fields added in a SSB configuration report and a SSB configurationadjustment may be shown in Table 2-2 below.

TABLE 2-2 Field Value and description BH SSB-TX-period Bit string, atransmission period of a SSB signal BH SSB-TX-resource Bit string, asub-frame position for transmission of a SSB signal

FIG. 47 shows an exemplary process showing that a node configures amapping relationship between a hop count and a SSB position for an IABnode.

The fields added in this process may be shown in Table 2-3 below.

TABLE 2-3 Field Value and description Mapping of SSB Bit string, arelationship between a SSB and hop order position in a half-frame and ahop count of the node (a specific hop count corresponding to a SSBresource in this configuration)

Furthermore, according to an embodiment, in a case that a link qualityof a backhaul link of the relay node is lower than a predeterminedthreshold, at least a part of the time resources for the transmission ofthe SSB may be adjusted to be used for reception for the SSB. Thepredetermined threshold may be configured by the donor node for therelay node.

In other words, in a case that the current route quality of the IAB nodeis lower than the threshold, the IAB node needs to increase SSB RXpositions to detect more candidate IAB nodes or donor nodes. Theconfigured TX SSB for the IAB node is muted to monitor other SSBpositions, without affecting other IAB nodes.

The exemplary process is shown in FIG. 48 . The donor node configures,for its child nodes, SSB TX muting threshold conditions and resourcepositions of SSB TX. In a case that the threshold condition issatisfied, the IAB node will monitor at the SSB TX.

The fields that should be added in radio resource control (RRC)signaling are as shown in Table 2-4 below.

TABLE 2-4 Field Value and description Muting threshold Bit string, alink state threshold triggering muting Muting BH SSB Bit string, a BHSSB position for which muting is position performed

Furthermore, in a case that the at least a part of the time resources isadjusted to be used for reception for the SSB, for an adjacent node ofthe relay node, corresponding time-frequency resources may be adjustedto be used for transmission for the SSB.

More specifically, the donor node may appropriately adjust SSB RX/TXpositions of two adjacent IAB nodes based on a route quality of the IABnodes and a load status of a cell. This process is shown in FIG. 49 .

The fields newly added in RRC signaling may be similar to the field ofMuting BH SSB position in Table 2-4.

In addition, the adjustment may be performed in the following manner:transmitting, in a case that the link quality of the backhaul link ofthe relay node is lower than a predetermined threshold, a request to thedonor node by the relay node; and configuring, by the donor node, moretime resources for reception of the SSB for the relay node based on therequest.

More specifically, in a case that a route quality of the IAB node islower than the threshold, the IAB node may actively request to beconfigured with more SSB monitoring positions, and the donor node mayindicate a SSB RX group based on configurations around the IAB node.This process is shown in FIG. 50 .

The fields newly added in muting SSB resources may be similar to thefield of Muting BH SSB position in Table 2-4.

According to the above embodiment, manners for configuring theSSBs/CSI-RSs of adjacent IAB nodes may be coordinated, such that theadjacent IAB nodes may discover each other.

Furthermore, in a case that the AC SSB positions and BH SSB positions ofone IAB node are orthogonal to each other, and the BH SSB TX and BH SSBRx of adjacent cells are coordinated with each other, since two adjacentIAB nodes have an overlapping coverage, UEs in the overlapping coveragemay suffer an interference by SSB (AC SSB or BH SSB) signals from aneighboring cell.

More specifically, as shown in FIG. 51A, since a distance between an IABdonor node and an IAB node is far, a signal power of the BH SSB islarge. If a main frequency band and a subcarrier frequency band used bythe IAB donor node and the IAB node adopt the same mode, their SSB modes(patterns) are the same. In this case, the BH SSB of the IAB donor nodeand the AC SSB of the IAB node are transmitted in the same time, and theBH SSB will affect monitoring of the AC SSB by the UE.

In addition, as shown in FIG. 51B, if an IAB node 1 and an IAB node 2have the same main frequency and the same subcarrier interval, the IABnode 1 transmits a BH SSB and the IAB node 2 transmits an AC SSB on thesame time-frequency resources. Since the power of the BH SSB isrelatively large, the BH SSB will influence the AC SSB.

In view of the above problems, according to an embodiment, theconfiguration information of the reference signal may include a mannerof transmitting a SSB for an access link and a SSB for a backhaul linkby an adjacent node. The manner may include: transmitting, by theadjacent node, the SSB for the access link and the SSB for the backhaullink through orthogonal time resources.

More specifically, if two adjacent IAB nodes have the same mainfrequency resources or the same subcarrier bandwidths, the BH and ACSSBs transmitted by the two IAB nodes are orthogonal. The BH SSBpositions of a parent IAB node may not be used to transmit the AC SSB bythe child IAB node.

The configuration process is shown in FIG. 52 and FIG. 53 . In a mannershown in FIG. 52 , an IAB donor node directly indicates positions wherethe surrounding IAB nodes may not transmit an AC SSB. In a manner shownin FIG. 53 , an IAB donor node directly indicates positions where IABnode 1 and IAB node 2 may not transmit an AC SSB.

The fields newly added in an indication of unavailable AC SSBs are asshown in Table 3-1 below.

TABLE 3-1 Field Value and description UnavailableACSSB Bit string,indicating AC SSB resources that an IAB node may not configure

According to another embodiment, a manner of transmitting a SSB for anaccess link and a SSB for a backhaul link by an adjacent node includes:transmitting, by the adjacent node, the SSB for the backhaul link usinga directional beam.

Since the position of the IAB node is fixed, a directional beam may beintroduced to transmit a SSB. In addition, a UE within the beamdirection range may be configured not to monitor a SSB on time-frequencyresources of the BH SSB.

As shown in FIG. 54 , when an IAB donor node detects that IAB node 1 andIAB node 2 have the same SSB mode, the IAB donor node may indicate theIAB node to transmit a SSB signal using the directional beam.

The fields newly added for a BH directional beam are shown in Table 3-2below.

TABLE 3-2 Field Value and description BH-SSB-Finerbeam-TXresource Bitstring, transmission time-frequency resources of a SSB directional beamBH-SSB-Finerbeam-RXresource Bit string, reception time-frequencyresources of a SSB directional beam BH-SSB-Finerbeam-TXdirection Bitstring, transmission direction configuration of a SSB directional beamBH-SSB-Finerbeam-period Bit string, SSB period configuration

In the above embodiment, by parameter configuration, it is possible tocoordinate to ensure that the UE is not interfered by a BH SSB of theneighboring IAB.

Furthermore, in a case that an IAB node receives a SSB signal or aCSI-RS signal, according to the existing cell access solution, a problemmay occur that a latency of a selected cell (due to too many hop counts)may not meet the requirements or the load of the selected cell isincreased.

Specifically, a manner that the UE performs cell access is as follows.Based on signal strength of a link, a cell with the strongest signalstrength is selected for access. In a case that the current link qualityis lower than a threshold, a cell with the best link quality is selectedto switch. In a case that the IAB node performs cell selection or routereselection, if the route selection is performed only based on the linkquality, it may cause a large transmission latency of the selectedroute, a heavy cell load or a low data rate of the route, resulting inre-switching of the IAB node or performance degradation. For example, asshown in FIG. 55 , if a link quality is taken as the only factor, RN3may select RN2 to connect, rather than selecting RN1 with a small hopcount, which may cause a large link transmission latency. In order toimprove performance and quality of the route reselection performed bythe IAB node, a solution for link reselection of the IAB node isprovided according to the following embodiments.

As shown in FIG. 2 , an electronic device 200 for wireless communicationaccording to an embodiment includes a processing circuitry 210. Theprocessing circuitry 210 includes a control unit 211 and an acquisitionunit 213. A configuration of the control unit 211 is similar to thatdescribed in the above embodiment, which is not repeated here.

The acquisition unit 213 is configured to acquire hop count informationindicating a relay hop count of a relay node from a donor node.

The hop count of an IAB node in an IAB topology may affect a selectionand a reselection for other IAB nodes. A definition of hop count and anindication of the hop count in the network should also be considered.Because the number and hop counts of IAB nodes that an IAB donor nodemay connect are uncertain, it is reasonable to calculate the hop countof the IAB node from the IAB donor node. As the IAB nodes expand, thehop counts are gradually increased.

Regarding a manner of indicating hop counts, according to an embodiment,a relay hop count of a relay node which transmits a reference signal canbe determined based on a predetermined correspondence between a resourceposition of the reference signal and the relay hop count. As describedabove, the reference signal may include, for example, a SSB and aCSI-RS. In addition, the reference signal used to determine hop countsmay also include a system information block signal such as a MIB or aSIB (which is a broadcast signal). The above predeterminedcorrespondence may be notified by the donor node to the relay node.

In this manner, hop count information is implicitly indicated. Morespecifically, there is a mapping between the hop count of the TAB nodeand the position for transmitting a BH SSB. When the TAB node 1 monitorsa SSB signal from the TAB node 2, the TAB node 1 knows the hop count ofthe TAB node 2 based on the position of the SSB. If the TAB node 1 joinsthe TAB node 2, just 1 is added to the hop count of the TAB node 1, andthen the TAB node 1 transmits a BH SSB at a SSB position correspondingto the hop count. It is assumed that the hop count of the IAB donor nodeis hop0, a hop count of an TAB node connected with the hop0 node (IABdonor node) is hop1, and a hop count of an TAB node connected with thehop1 node is hop2, and so on.

As shown in FIG. 56 , the hop count information is implicitly indicatedto a child TAB node by discovering resource positions of a signal, orresource positions of the synchronization signal, or resource positionsof a MIB/SIB signal. The UE or the child TAB node obtains the hop countinformation based on the resource positions of the received signal. Theresource position information may be configured by the IAB donor node,and the mapping list (signal resource and hop count) is transmitted tothe child TAB node.

Table 4-1 shows an example of a mapping list of signal resources and hopcounts.

TABLE 4-1 Hop count Resource Hop count 1 Resource group 1 Hop count 2Resource group 1 . . . . . .

According to another embodiment, the acquisition unit 213 may also beconfigured to acquire the hop count from master system informationblocks, radio resource control signaling or the reference signaltransmitted by a node.

In other words, hop count information may be indicated explicitly.

More specifically, the hop count information of the TAB node may bestored in MIB information, and the TAB node may obtain the hop count ofthe connected TAB node by monitoring the MIB information of theconnected IAB node.

Examples of the fields that should be added in the MIB are shown inTable 4-2 below.

TABLE 4-2 Field Value and description hop-order Bit string (length of 3to 4), a hop count of an IAB node

Alternatively, the parent IAB node or the IAB donor node may indicate ahop count of a child IAB node by RRC signaling (the indication may bethe hop count of the parent IAB node or the hop count of the child IABnode).

Examples of the fields that should be added in RRCReconfiguration areshown in Table 4-3 below.

TABLE 4-3 Field Value and description hop-order Bit string (length of 3to 4), a hop count of an IAB node

Alternatively, the parent IAB node or the IAB donor node may indicateinformation of its hop by a discovery signal (SSB signal or CSI-RSsignal), such that the IAB may select an appropriate parent IAB node orIAB donor node based on the discovery signal.

Examples of the fields that should be added in the discovery signal areshown in

Table 4-4 below.

TABLE 4-4 Field Value and description hop-order Bit string (length of 3to 4), a hop count of an IAB node

Furthermore, according to an embodiment, reselection of a backhaul linkmay also be performed based on the hop count information.

As shown in FIG. 3 , an electronic device 300 for wireless communicationaccording to an embodiment includes a processing circuitry 310. Theprocessing circuitry 310 includes a control unit 311, an acquisitionunit 313 and a reselection unit 315. Configurations of the control unit311 and the acquisition unit 313 are similar to that described in theabove embodiment, which are not repeated here.

The reselection unit 315 is configured to perform reselection of abackhaul link based on the following conditions: hop counts of a currentconnection node and a candidate connection code; and/or link qualitiesof a current connection node and a candidate connection node.

More specifically, the reselection unit 315 may be configured todetermine, in a case that a condition of the candidate connection nodeis better than that of the current connection node, to switch to thecandidate connection node.

According to the present embodiment, the IAB node performs switchingonce a suitable link is detected. As shown in FIG. 57 , the IAB nodeobtains a link quality and a hop count of a candidate IAB node based ona SSB signal. First, it may be determined whether the hop count isgreater than the current hop count; if not, it is determined whether thelink quality is better than the current link quality. If the linkquality is better than the current link quality, a link reselection isperformed. If the measured link quality is not better than the currentlink quality, the current link is maintained and monitoring of candidateIAB nodes is continued. If the hop count of the candidate node isgreater than the hop count of the current node, it is determined whetherthe current link quality is less than a certain threshold (a need toswitch urgently). If the current link quality is less than the currentthreshold, the link quality of the candidate node is compared with thelink quality of the current node. If the link quality of the candidatenode is greater than the link quality of the current node, the switchingis performed. The threshold condition of link quality may be configuredby the parent IAB node or may be configured by the IAB node itself.

FIG. 58 shows a signaling flow of this exemplary manner. In thisexample, the threshold condition is configured by the donor node or theparent IAB node.

Correspondingly, the newly added RRC fields may be as shown in Table4-5.

TABLE 4-5 Field Value and description threshold1 Bit string, used for acase that a hop count of a selected IAB node is less than or equal to ahop count of the current parent IAB node, if a link quality of theselected IAB node is greater than the threshold, a route reselection isperformed threshold2 Bit string, in a case that the current link qualityis less than the threshold, it is determined whether an IAB node whosehop count is greater than a hop count of the current parent IAB node isselected

Furthermore, the reselection unit 315 may also be configured to select acandidate connection node to be switched to, based on the conditions ofmultiple candidate connection nodes measured in a given time window.

In other words, multiple candidate nodes are measured in a given timewindow, and an optimal node is selected for switching. As shown in FIG.59 , the IAB node obtains a link quality and a hop count of a candidateIAB node based on a SSB signal. In a case that the link quality of theIAB node is lower than a threshold, the IAB node initiates the timewindow and counts information of all candidate routes in the timewindow. An optimal route is found based on the relevant parameters. Ifthe optimal link quality is greater than the current route quality, theswitching is selected; otherwise, the current route is maintained. Thethreshold condition may be configured by the parent IAB node, or may beconfigured by the node itself. In a case that a measured link quality ofa certain link is higher than the threshold, the node is added into acandidate node list (as shown in Table 4-6 below), and the listinformation may be updated periodically, to avoid keeping a node whoselink quality gets worse in the candidate list.

TABLE 4-6 RSRP (reference signal ID of candidate node Hop count receivedpower) Node 1 Node 2 . . .

FIG. 60 shows a signaling flow of this exemplary manner. In thisexample, the threshold condition is configured by the donor node or theparent IAB node.

Correspondingly, the newly added RRC fields may be as shown in Table4-7.

TABLE 4-7 Field Value and description Threshold Bit string, in a casethat RSRP is greater than this threshold, it is determined that anoptimal link is selected from the list

Furthermore, the reselection unit 315 may also be configured to reportthe conditions of the multiple candidate connection nodes measured in agiven time window to the donor node, and the donor node may select acandidate connection node to be switched to.

In other words, the switching may be assisted by the IAB donor node. Asshown in FIG. 61 , the IAB node informs the IAB donor node ofinformation of all candidate IAB nodes, and the IAB donor node assiststhe IAB node in determining which candidate cell to be switched to. Inorder to reduce signaling overhead of the IAB node for reportingcandidate BHs to the IAB donor node, the IAB node may measure a linkquality of a candidate node. In a case that the measured link quality isgreater than the threshold, the candidate node is added in the candidatenode list.

A threshold condition of the link quality of the current route may beset. In a case that the current link quality is lower than a certainthreshold, the IAB node reports a candidate link set and the measuredlink quality to the IAB donor node. The IAB donor node indicates the IABnode whether to perform a switching process or which link is to beselected for switching, and transmits context information of the IABnode to the selected candidate IAB node, to assist a route reselectionof the IAB node. The threshold condition may be configured by the parentIAB node or may be configured by the IAB node itself. In a case that ameasured link quality of a certain link is higher than the threshold,the node may be added into the candidate node list, and the listinformation may be updated periodically, to avoid keeping a link whosequality gets worse in the candidate list.

FIG. 62 shows a signaling flow of this exemplary manner. In thisexample, the threshold condition is configured by the donor node or theparent IAB node.

Correspondingly, the newly added RRC fields may be as shown in Table4-8.

TABLE 4-8 Field Value and description Threshold3 Bit string, in a casethat a measured RSRP of a candidate link is greater than this threshold,the candidate link is added into a candidate link list Threshold4 Bitstring, in a case that the current link quality RSRP is less than thisthreshold, candidate link information is reported to IAB donor node

With a manner and configuration for the link selection according to theabove embodiment, a more efficient and high-quality IAB link reselectionmanner can be provided.

Furthermore, as the hop counts of network increase, synchronizationerrors will accumulate as the topology structure expands, and there is ahigher requirement of synchronization accuracy of each link. Accordingto the existing synchronization method based on a timing advance (TA),it is difficult to meet the requirement of synchronization accuracy.Thus, the embodiments described below relate to a solution for improvingsynchronization accuracy.

As shown in FIG. 4 , an electronic device 400 for wireless communicationaccording to an embodiment includes a processing circuitry 410. Theprocessing circuitry 410 includes a control unit 411 and a determinationunit 413. A configuration of the control unit 411 is similar to thatdescribed in the above embodiment, which is not repeated here.

The determination unit 413 is configured to determine, based on a timeoffset between signals of different nodes connected via a backhaul link,an adjustment of synchronization time for at least one node of thedifferent nodes. The adjustment may include adjusting, in a case thatthe offset between a Synchronization Signal Block SSB for a superiornode and a Synchronization Signal Block SSB for a subordinate node whichare connected via a backhaul link exceeds a predetermined threshold,synchronization time for the subordinate node.

Conventionally, a manner for a UE to obtain synchronization is to obtaina position of sub-frame 0 in a frame by monitoring a SSB signal. In FIG.63 , in an IAB multi-hop topology structure, both DN1 and RN1 need totransmit a BH SSB, and then, DN1 and RN1 may obtain a position ofsub-frame #0 in a frame by monitoring BH SSB signals from each other. Ifan offset between the position of sub-frame #0 of one node and thedetected sub-frame #0 of the other node is greater than a threshold, thechild IAB node may readjust synchronization time, for example, bychanging the TA value.

Furthermore, a configuration of the reference signal for a discovery ofan IAB node may also be adjusted based on the synchronization situation.

As shown in FIG. 5 , an electronic device 500 for wireless communicationaccording to an embodiment includes a processing circuitry 510. Theprocessing circuitry 510 includes a control unit 511, a determinationunit 513 and an adjustment unit 515. Configurations of the control unit511 and the determination unit 513 are similar to those described in theabove embodiment, which is not repeated here.

The adjustment unit 515 is configured to: in a case that the offsetbetween the SSB for the superior node and the SSB for the subordinatenode is greater than a predetermined upper limit, with respect to thesubordinate node, reduce a monitoring period for the SSB or increasemonitoring positions for the SSB.

Alternatively, the adjustment unit 515 may be configured to: in a casethat the offset between the SSB for the superior node and the SSB forthe subordinate node is lower than a predetermined lower limit, withrespect to the subordinate node, increase a monitoring period for theSSB or reduce monitoring positions for the SSB.

For example, the parent IAB node may configure a period of monitoringthe child BH SSB and a position of monitoring the SSB by itself based onthe current timing accuracy.

If the current accuracy is unstable and a large offset occurs, theperiod of monitoring the SSB may be reduced and the positions ofmonitoring the SSB may be increased. If the current accuracy of the SSBis stable and an offset value for each measurement is small, the periodof monitoring the SSB may be increased and the positions of monitoringthe SSB may be reduced.

An exemplary manner of bi-directional SSB monitoring and timingcalculation is described above. Referring back to FIG. 4 , according toan embodiment, the adjustment determined by the determination unit 413may also include: adjusting, in a case that the offset between aSynchronization Signal Block SSB from a first node and a SynchronizationSignal Block SSB from a third node which are received by a second nodeexceeds a predetermined threshold, synchronization time for the thirdnode. The first node is a superior node for the second node, and thesecond node is a superior node for the third node.

As shown in FIG. 64 , RN1 receives data from DN1 and RN2 at the sametime point. In a case that there is a time offset between data receivedfrom DN1 and data received from RN2, if the offset is greater than acertain threshold, RN1 readjusts RN2 to synchronize RN2 with DN1.

Furthermore, in a case that the offset is greater than the threshold,first, RN1 may determine an alignment with the parent IAB node, thenadjusts its own time position for a SSB, and then adjusts asynchronization time for the child BH. The threshold may be configuredby RN1 itself.

In addition, the second node may also adjust a transition gap between anuplink and a downlink (UL-DL transition gap) based on the above offset.The transition gap may be configured by the donor node or may beconfigured by a superior node for the second node. This transition gapmay also be referred to as receiving-transmitting switching time or gap(RX TX switching time/gap). For a time division duplex (TDD) frame, theTx/Rx gap (TTG) and an Rx/Tx gap (RTG) are set between a downlink burst(DL burst) and an uplink burst (UL burst) to support areceiving-transmitting transition of a base station. For an IAB node,similar gaps may be set to ensure the receiving-transmitting transitionbetween the relay nodes or the donor nodes. By adjusting the transitiongap based on the synchronization offset, the receiving-transmittingtransition of the IAB node can be ensured.

Reference is still made to FIG. 4 , according to an embodiment, thedetermination unit 413 may determine an adjustment of synchronizationtime in the following manner: transmitting, by a first node, timingconfiguration to a second node connected with the first node via abackhaul link; transmitting, by the second node, a synchronizationmaintenance signal to the first node based on the timing configuration;and determining, by the first node, an adjustment of synchronizationtime for the first node or the second node based on the timingconfiguration and a timing for the synchronization maintenance signal.

In the present embodiment, a timing maintenance signal is introduced forthe backhaul link. As shown in FIG. 65 , a new timing synchronizationsignal is introduced. In this way, the parent IAB node configures, forthe child IAB node, a synchronization maintenance signal fortime-frequency resource transmission, and the parent IAB node starts atimer at the corresponding time position. When the parent IAB nodereceives the synchronization maintenance signal, the timer is terminatedand duration is calculated. An offset value between the duration and theprevious value is compared with a threshold, and if the offset value isgreater than the threshold, the TA is readjusted to providesynchronization accuracy.

FIG. 66 shows a signaling flow of this exemplary manner. The field oftiming maintenance configuration may include time-frequency resources ofthe timing maintenance signal, a period of transmitting the timingmaintenance signal, and a threshold for configuring and adjusting a TA.

Correspondingly, the newly added RRC fields may be as shown in Table 5.

TABLE 5 Field Value and description Timing maintenance Bit string,indicating time-frequency configuration resources and a period fortransmitting the synchronization maintenance signal

According to the above embodiment, more accurate synchronization betweenIAB nodes can be implemented.

In above descriptions of the device embodiments, it is apparent thatsome processes and methods are also disclosed. Next, a method forwireless communication according to an embodiment of the presentdisclosure is described without repeating the details described above.

As shown in FIG. 6 , a method for wireless communication according to anembodiment includes step S610 of transmitting or receiving configurationinformation related to configuration of a reference signal for adiscovery process of an Integrated Access and Backhaul link IAB node.

Furthermore, FIG. 7 shows a configuration example of an electronicdevice for wireless communication according to an embodiment. As shownin FIG. 7 , the electronic device 700 includes a processing circuitry710. The processing circuitry 710 includes an acquisition unit 711.

The acquisition unit 711 is configured to acquire hop count informationindicating a relay hop count of a relay node from a donor node. Thedonor node is an IAB node which is in wired connection with a corenetwork, and the relay node is an IAB node which is not in wiredconnection with the core network.

Acquiring the hop count information may include: determining, based on apredetermined correspondence between a time resource position of a SSBand a relay hop count, a hop count of a relay node that transmits theSSB.

Acquiring the hop count information may include: acquiring the hop countinformation from master system information blocks, radio resourcecontrol signaling or a reference signal for a discovery process of anIAB node transmitted by the relay node.

FIG. 8 shows a configuration example of an electronic device forwireless communication according to another embodiment. As shown in FIG.8 , the electronic device 800 includes a processing circuitry 810. Theprocessing circuitry 810 includes an acquisition unit 811 and areselection unit 813. The acquisition unit 811 is similar to theacquisition unit 711 described above.

The reselection unit 813 is configured to perform reselection of abackhaul link based on hop counts of a current connection node and acandidate connection code; and/or link qualities of a current connectionnode and a candidate connection node.

More specially, the reselection unit 813 may be configured to:determine, in a case that a condition of the candidate connection nodeis better than that of the current connection node, to switch to thecandidate connection node; select a candidate connection node to beswitched to, based on the conditions of multiple candidate connectionnodes measured in a given time window; or report the conditions of themultiple candidate connection nodes measured in a given time window tothe donor node, and the donor node may select a candidate connectionnode to be switched to.

FIG. 9 shows a process example of the corresponding method for wirelesscommunication. As shown in FIG. 9 , a method for wireless communicationincludes step S910 of acquiring hop count information indicating a relayhop count of a relay node from a donor node. The donor node is an IABnode which is in wired connection with a core network, and the relaynode is an IAB node which is not in wired connection with the corenetwork.

Furthermore, FIG. 10 shows a configuration example of an electronicdevice for wireless communication according to an embodiment. As shownin FIG. 10 , the electronic device 1000 includes a processing circuitry1010. The processing circuitry 1010 includes a determination unit 1011.

The determination unit 1011 is configured to determine, based on a timeoffset between signals of different nodes connected via a backhaul link,an adjustment of synchronization time for at least one node of thedifferent nodes.

The adjustment may include adjusting, in a case that an offset between aSSB for a superior node and a SSB for a subordinate node which areconnected via a backhaul link exceeds a predetermined threshold,synchronization time for the subordinate node.

The determination unit 1011 may determine the adjustment as: adjusting,in a case that an offset between a Synchronization Signal Block SSB froma first node and a Synchronization Signal Block SSB from a third nodewhich are received by a second node is greater than a predeterminedthreshold, synchronization time for the third node. The first node, thesecond node and the third node are connected via a backhaul link, thefirst node is a superior node for the second node, and the second nodeis a superior node for the third node.

The determination unit 1011 may further determine the adjustment as:adjusting, by the second node, a transition gap between an uplink and adownlink based on the offset. The transition gap can be configured by adonor node or by a superior node for the second node.

The determination unit 1011 may be configured to determine theadjustment in the following manner: transmitting, by a first node,timing configuration to a second node connected with the first node viaa backhaul link; transmitting, by the second node, a synchronizationmaintenance signal to the first node based on the timing configuration;and determining, by the first node, an adjustment of synchronizationtime for the first node or the second node based on the timingconfiguration and a timing for the synchronization maintenance signal.

FIG. 11 shows a configuration example of an electronic device forwireless communication according to another embodiment. As shown in FIG.11 , an electronic device 1100 includes a processing circuitry 1110. Theprocessing circuitry 1110 includes a determination unit 1111 and anadjustment unit 1113. The determination unit 1111 is similar to thedetermination unit 1011 described above.

The adjustment unit 1113 is configured to: in a case that an offsetbetween the SSB for the superior node and the SSB for the subordinatenode is greater than a predetermined upper limit, cause the subordinatenode to reduce a monitoring period for the SSB or increase monitoringpositions for the SSB; and/or in a case that an offset between the SSBfor the superior node and the SSB for the subordinate node is lower thana predetermined lower limit, cause the subordinate node to increase amonitoring period for the SSB or reduce monitoring positions for theSSB.

FIG. 12 shows a process example of the corresponding method for wirelesscommunication. As shown in FIG. 12 , a method for wireless communicationincludes step S1210 of determining, based on a time offset betweensignals of different nodes connected via a backhaul link, an adjustmentof synchronization time for at least one node of the different nodes.

According to an embodiment of the present disclosure, acomputer-readable medium is further provided. The computer-readablemedium includes executable instructions which, when executed by aninformation processing apparatus, cause the information processingapparatus to implement the method according to the above embodiments.

As an example, various steps of the above methods and various modulesand/or units of the above devices may be implemented by software,firmware, hardware, or a combination thereof. When implemented bysoftware or firmware, a program constituting software for implementingthe above method may be installed from a storage medium or a network toa computer (for example, a general-purpose computer 1300 shown in FIG.13 ) having a dedicated hardware structure, which, when installed withvarious programs, may perform various functions and the like.

In FIG. 13 , a computation processing unit (CPU) 1301 may performvarious processes based on a program stored in a read-only memory (ROM)1302 or a program loaded in a random-access memory (RAM) 1303 from astorage section 1308. Data required for various processing and the likeof the CPU 1301 may be stored in the RAM 1303 as needed. The CPU 1301,the ROM 1302 and the RAM 1303 are linked to each other via a bus 1304.An input/output interface 1305 is also linked to the bus 1304.

The following components are linked to the input/output interface 1305:an input section 1306 (including a keyboard, a mouse, and the like), anoutput section 1307 (including a display such as a cathode ray tube(CRT), a liquid crystal display (LCD) and the like, and a loudspeakerand the like), a storage section 1308 (including a hard disk and thelike), and a communication section 1309 (including a network interfacecard such as a LAN card, a modem and the like). The communicationsection 1309 performs communication processing via a network such as theInternet. A driver 1310 may also be linked to the input/output interface1305 as needed. A removable medium 1311 such as a magnetic disk, anoptical disk, a magnetic optical disk, a semiconductor memory and thelike is installed onto the driver 1310 as needed, such that a computerprogram read therefrom is installed into the storage section 1308 asneeded.

In a case that the above series of processing are implemented bysoftware, programs constituting the software are installed from anetwork such as the Internet or a storage medium such as the removablemedium 1311.

Those skilled in the art should understand that the storage medium isnot limited to the removable medium 1311 shown in FIG. 13 which storesprograms and is distributed separately from the apparatus to provide theprograms to a user. The removable medium 1311 may be, for example, amagnetic disk (including a floppy disk (registered trademark)), anoptical disk (including a compact disk read-only memory (CD-ROM) and adigital versatile disk (DVD)), a magneto-optical disk (including a minidisc (MD) (registered trademark)), and a semiconductor memory.Alternatively, the storage medium may be an ROM 1302, a hard diskincluded in the storage section 1308 in which programs are stored, andthe like, and is distributed to the user along with an apparatus inwhich they are incorporated.

An embodiment according to the present disclosure also relates to aprogram product storing a machine-readable instruction code. The methodaccording to the above embodiments of the present disclosure may beperformed when the instruction code is read and executed by a machine.

Accordingly, a storage medium for carrying the program product in whicha machine-readable instruction code is stored is also provided in thepresent disclosure. The storage medium includes, but is not limited to,a soft disk, an optical disk, a magnetic optical disk, a memory card, amemory stick and the like.

The embodiments according to the present disclosure may further relateto the following electronic apparatus. In a case that the electronicapparatus is applied for a base station side, the electronic apparatusmay be implemented as a gNB of any type, and an evolved node B (eNB)such as a macro eNB and a small eNB. The small eNB may be an eNBcovering a cell smaller than a macro cell, such as a pico eNB, a microeNB and a home (femto) eNB. Alternatively, the electronic apparatus maybe implemented as any other types of base stations, such as a NodeB anda base transceiver station (BTS). The electronic apparatus may include:a main body (which is also referred to as a base station apparatus)configured to control wireless communication; and one or more remoteradio heads (RRHs) arranged at a place different from the main body. Inaddition, various types of terminals described below may operate as basestations by temporarily or semi-persistently performing functions of abase station.

In a case that the electronic apparatus is used at a user equipmentside, the electronic apparatus may be implemented as a mobile terminal(such as a smartphone, a tablet personal computer (PC), a notebook PC, aportable game terminal, a portable/dongle-type mobile router, and adigital camera device) or an in-vehicle terminal (such as a vehiclenavigation device). Furthermore, the electronic apparatus may be awireless communication module (such as an integrated circuit moduleincluding a single chip or multiple chips) mounted on each of theterminals described above.

[Application Example of a Terminal Device]

FIG. 14 is a block diagram illustrating an example of a schematicconfiguration of a smartphone 2500 to which the technology according tothe present disclosure may be applied. The smartphone 2500 includes aprocessor 2501, a memory 2502, a storage device 2503, an externalconnection interface 2504, a camera device 2506, a sensor 2507, amicrophone 2508, an input device 2509, a display device 2510, a speaker2511, a wireless communication interface 2512, one or more antennaswitches 2515, one or more antennas 2516, a bus 2517, a battery 2518,and an auxiliary controller 2519.

The processor 2501 may be for example a CPU or a System On Chip (SoC),and control functions of an application layer and another layer of thesmartphone 2500. The memory 2502 includes an RAM and an ROM, and storesdata, and programs executed by the processor 2501. The storage device2503 may include a storage medium, such as a semiconductor memory and ahard disk. The external connection interface 2504 is an interface forconnecting an external device (such as a memory card and a universalserial bus (USB) device) to the smartphone 2500.

The camera device 2506 includes an image sensor (such as a chargecoupled device (CCD) and a complementary metal oxide semiconductor(CMOS)) and generates a captured image. The sensor 2507 may include aset of sensors, such as a measurement sensor, a gyroscope sensor, ageomagnetic sensor and an acceleration sensor. The microphone 2508converts sound input into the smartphone 2500 into an audio signal. Theinput device 2509 includes for example a touch sensor configured todetect touch on a screen of the display device 2510, a keypad, akeyboard, a button or a switch, and receives an operation or informationinput from a user equipment. The display device 2510 includes a screen(such as a liquid crystal display (LCD) and an organic light emittingdiode (OLED) display), and displays an output image of the smartphone2500. The speaker 2511 converts the audio signal output from thesmartphone 2500 into sound.

The wireless communication interface 2512 supports any cellularcommunication solution (such as LET and LTE-Advanced), and performswireless communication. The wireless communication interface 2512 maygenerally include, for example, a BB processor 2513 and an RF circuit2514. The BB processor 2513 may perform, for example, encoding/decoding,modulation/demodulation, and multiplexing/demultiplexing, and performsvarious types of signal processing for wireless communication. Inaddition, the RF circuit 2514 may include a frequency mixer, a filterand an amplifier, and transmits and receives a radio signal via theantenna 2516. The wireless communication interface 2512 may be a chipmodule on which the BB processor 2513 and the RF circuit 2514 areintegrated. The wireless communication interface 2512 may includemultiple BB processors 2513 and multiple RF circuits 2514, as shown inFIG. 14 . Although FIG. 14 shows an example in which the wirelesscommunication interface 2512 includes multiple BB processors 2513 andmultiple RF circuits 2514, the wireless communication interface 2512 mayalso include a single BB processor 2513 or a single RF circuit 2514.

Furthermore, in addition to a cellular communication solution, thewireless communication interface 2512 may support another type ofwireless communication solution such as a short-distance wirelesscommunication solution, a near field communication solution, and awireless local region network (LAN) solution. In this case, the wirelesscommunication interface 2512 may include the BB processor 2513 and theRF circuit 2514 for each wireless communication solution.

Each of the antenna switches 2515 switches connection destinations ofthe antennas 2516 among multiple circuits (for example, circuits fordifferent wireless communication solutions) included in the wirelesscommunication interface 2512.

Each of the antennas 2516 includes a single antenna element or multipleantenna elements (such as multiple antenna elements included in a MIMOantenna), and is used for transmitting and receiving a radio signal bythe wireless communication interface 2512. The smartphone 2500 mayinclude multiple antennas 2516, as shown in FIG. 14 . Although FIG. 14shows an example in which the smartphone 2500 includes multiple antennas2516, the smartphone 2500 may also include a single antenna 2516.

Furthermore, the smartphone 2500 may include the antenna 2516 for eachwireless communication solution. In this case, the antenna switch 2515may be omitted from the configuration of the smartphone 2500.

The bus 2517 connects the processor 2501, the memory 2502, the storagedevice 2503, the external connection interface 2504, the camera device2506, the sensor 2507, the microphone 2508, the input device 2509, thedisplay device 2510, the speaker 2511, the wireless communicationinterface 2512, and the auxiliary controller 2519 to each other. Thebattery 2518 supplies power to each block of the smartphone 2500 shownin FIG. 14 via feeder lines which are partially shown with dashed linesin figure. The auxiliary controller 2519, for example, operates aminimum necessary function of the smartphone 2500, for example, in asleep mode.

In the smartphone 2500 shown in FIG. 14 , a transceiver device of anapparatus for a user equipment side according to the embodiments of thepresent disclosure may be implemented by the wireless communicationinterface 2512. At least a part of the functions of a processing circuitand/or various units of the electronic device or information processingapparatus for the user equipment side according to the embodiments ofthe present disclosure may also be implemented by the processor 2501 orthe auxiliary controller 2519. For example, power consumption of thebattery 2518 may be reduced by performing a part of the functions of theprocessor 2501 by the auxiliary controller 2519. Furthermore, theprocessor 2501 or the auxiliary controller 2519 may perform at least apart of the functions of the processing circuit and/or various units ofthe electronic device or information processing apparatus for the userequipment side according to the embodiments of the present disclosure,by executing a program stored in the memory 2502 or the storage device2503.

[Application Example of a Base Station]

FIG. 15 is a block diagram showing an example of a schematicconfiguration of a gNB to which the technology according to the presentdisclosure may be applied. A gNB 2300 includes multiple antennas 2310,and a base station apparatus 2320. The base station apparatus 2320 maybe connected to each antenna 2310 via a radio frequency (RF) cable.

Each of the antennas 2310 includes a single antenna element or multipleelements (such as multiple antenna elements included in a multiple inputmultiple output (MIMO) antenna), and is used for transmitting andreceiving a radio signal by the base station apparatus 2320. The gNB2300 may include multiple antennas 2310, as shown in FIG. 15 . Forexample, the multiple antennas 2310 may be compatible with multiplefrequency bands used by the gNB 2300.

The base station apparatus 2320 includes a controller 2321, a memory2322, a network interface 2323, and a wireless communication interface2325.

The controller 2321 may be, for example, a CPU or a DSP, and operatesvarious functions of a higher layer of the base station apparatus 2320.For example, the controller 2321 generates a data packet based on datain a signal processed by the wireless communication interface 2325 andtransfers the generated packet via the network interface 2323. Thecontroller 2321 may bundle data from multiple baseband processors togenerate a bundled packet and transfers the generated bundled packet.The controller 2321 may have a logic function that performs, forexample, radio resource control, wireless bearer control, mobilitymanagement, admission control, and scheduling. The control may beperformed in conjunction with an adjacent gNB or a core network node.The memory 2322 includes an RAM and an ROM, and stores a program that isexecuted by the controller 2321 and various types of control data (suchas a terminal list, transmission power data, and scheduling data).

The network interface 2323 is a communication interface for connectingthe base station apparatus 2320 to a core network 2324. The controller2321 may communication with the core network node or another gNB via thenetwork interface 2323. In that case, the gNB 2300 and the core networknode or another gNB may be connected to each other through a logicalinterface (such as an S1 interface and an X2 interface). The networkinterface 2323 may also be a wired communication interface, or awireless communication interface for radio backhaul. If the networkinterface 2323 is a wireless communication interface, the networkinterface 2323 may use a higher frequency band for wirelesscommunication as compared with the frequency band used by the wirelesscommunication interface 2325.

The wireless communication interface 2325 supports any cellularcommunication solution (such as long term evolution (LTE) andLTE-Advanced), and provides a wireless connection to a terminalpositioned in a cell of the gNB 2300 via the antenna 2310. The wirelesscommunication interface 2325 may generally include, for example, a BBprocessor 2326 and an RF circuit 2327. The BB processor 2326 mayperform, for example encoding/decoding, modulation/demodulation andmultiplexing/demultiplexing, and perform various types of signalprocessing of a layer (for example L1, medium access control (MAC),radio link control (RLC) and packet data convergence protocol (PDCP)).The BB processor 2326 may have a part or all of the above-describedlogical functions instead of the controller 2321. The BB processor 2326may be a memory storing communication control programs, or a moduleincluding a processor and a related circuit which are configured toexecute programs. The function of the BB processor 2326 may be changedthrough program updating. The module may be a card or a blade insertedinto a slot of the base station apparatus 2320. Alternatively, themodule may also be a chip that is mounted on the card or the blade. Inaddition, the RF circuit 2327 may include, for example, a frequencymixer, a filter, and an amplifier, and transmits and receives a radiosignal via the antenna 2310.

The wireless communication interface 2325 may include the multiple BBprocessors 2326, as shown in FIG. 15 . For example, the multiple BBprocessors 2326 may be compatible with multiple frequency bands used bythe gNB 2300. As shown in FIG. 15 , the wireless communication interface2325 may include multiple RF circuits 2327. For example, the multiple RFcircuits 2327 may be compatible with multiple antenna elements. AlthoughFIG. 15 shows an example in which the wireless communication interface2325 includes multiple BB processors 2326 and multiple RF circuits 2327,the wireless communication interface 2325 may also include a single BBprocessor 2326 or a single RF circuit 2327.

In the eNB 2300 shown in FIG. 15 , a transceiving device of the wirelesscommunication apparatus for the base station side may be implemented bythe wireless communication interface 2325. At least a part of thefunctions of the processing circuit and/or various units of theelectronic device or the wireless communication apparatus for the basestation side may also be implemented by the controller 2321. Forexample, the controller 2321 may perform at least a part of thefunctions of the processing circuit and/or various units of theelectronic device or the wireless communication apparatus for the basestation side, by executing a program stored in the memory 2322.

In the above description of specific embodiments of the presentdisclosure, the features described and/or illustrated for one embodimentmay be used in one or more other embodiments in the same or similarmanner, may be combined with features in the other embodiments, or mayreplace the features in the other embodiments.

It should be emphasized that the term “including/comprising”, when usedherein, refers to the presence of a feature, an element, a step or acomponent, but does not exclude the presence or addition of one or moreother features, elements, steps or components.

In the above embodiments and examples, reference numerals composed ofnumber are used to indicate each step and/or unit. It will be understoodby those of ordinary skill in the art that these reference numerals arefor purpose of illustration and drawing and are not indicative of theorder or any other limitations thereof.

Furthermore, the method according to the present disclosure is notlimited to being executed in the chronological order described in thespecification, or may be executed in other chronological order, inparallel or independently. Therefore, the order of execution of themethod described in this specification does not limit the technicalscope of the present disclosure.

Although the present disclosure has been disclosed above through thedescription of specific embodiments of the present disclosure, it shouldbe understood that all the embodiments and examples described above areillustrative and not restrictive. Various modifications, improvementsand equivalents may be made to the present disclosure by those skilledin the art within the scope and spirit of accompanying claims. Thesemodifications, improvements or equivalents should fall within the scopeof protection of the present disclosure.

Furthermore, an embodiment according to the present disclosure furtherincludes:

(1) An electronic device for wireless communication, comprisingprocessing circuitry configured to:

preform control to transmit or receive configuration information relatedto configuration of a reference signal for a discovery process of anIntegrated Access and Backhaul link IAB node.

(2) The electronic device according to (1), wherein the reference signalcomprises Synchronization Signal Block SSBs, and

the configuration information comprises a multiplexing manner of a SSBfor an access link and a SSB for a backhaul link.

(3) The electronic device according to (2), wherein the multiplexingmanner comprises:

allocating a part of SSB resource positions in a period of the SSB forthe access link to the SSB for the backhaul link; and/or

increasing a period of the SSB for the access link, and arranging theSSB for the backhaul link in an increased part of the period.

(4) The electronic device according to (2), wherein the multiplexingmanner is adjusted based on an access performance of a user equipment,the adjusting comprises:

in a case that the access performance decreases, increasing a SSB forthe access link.

(5) The electronic device according to (4), wherein the adjusting istriggered in a case that an access latency of the user equipment exceedsa predetermined threshold.

(6) The electronic device according to (2), wherein the multiplexingmanner comprises:

applying different power levels to the SSB for the access link and theSSB for the backhaul link; and/or

setting a specific SSB resource position as the SSB for the access link.

(7) The electronic device according to (1), wherein the reference signalcomprises Channel State Information Reference Signal CSI-RSs, and

the configuration information comprises a multiplexing manner of aCSI-RS for an access link and a CSI-RS for a backhaul link.

(8) The electronic device according to (7), wherein the multiplexingmanner comprises:

transmitting the CSI-RS for the backhaul link using a directional beam,and multiplexing time-frequency resources of the CSI-RS for the accesslink and the CSI-RS for the backhaul link.

(9) The electronic device according to (8), wherein the node comprises adonor node and a relay node, and the multiplexing manner is determinedin the following manner:

configuring, by the donor node, parameter information of a directionalbeam for the relay node based on physical position information of therelay node and a connection relationship among the relay nodes;

configuring, by the donor node, parameter information of directionalbeams for the relay node and a candidate node around the relay nodebased on direction information related to the candidate node which isdetected and reported by the relay node; or

configuring, by the relay node, parameter information of a directionalbeam based on direction information related to a surrounding candidatenode which is detected by the relay node, and reporting, by the relaynode, the configured parameter information to the donor node.

(10) The electronic device according to (9), wherein the physicalposition information of the relay node and the connection relationshipsamong the relay nodes are reported by the relay node to the donor node.

(11) The electronic device according to (7), wherein the multiplexingmanner comprises:

transmitting the CSI-RS for the backhaul link in an omnidirectionalmode, and adopting orthogonal time-frequency resources for the CSI-RSfor the access link and the CSI-RS for the backhaul link.

(12) The electronic device according to (11), wherein the node comprisesa donor node and a relay node, and the multiplexing manner is determinedin the following manner:

configuring, by the donor node, the time-frequency resources for therelay node based on physical position information of the relay node anda connection relationship among the relay nodes; or

configuring, by the relay node, the time-frequency resources for asubordinate node of the relay node, and reporting, by the relay node,the configured time-frequency resources to the donor node.

(13) The electronic device according to (1), wherein the referencesignal comprises Synchronization Signal Block SSBs, and

the configuration information comprises a multiplexing manner oftransmission and/or reception for the SSB.

(14) The electronic device according to (13), wherein the multiplexingmanner comprises:

time resources for transmission of SSBs of djacent nodes beingorthogonal.

(15) The electronic device according to (14), wherein the node comprisesa donor node and a relay node, and the multiplexing manner is determinedin the following manner:

configuring, by the donor node, time resources for transmission of theSSB of the relay node based on physical position information of therelay node and a connection relationship among the relay nodes;

configuring, by the relay node, the time resources for a subordinatenode of the relay node, and reporting, by the relay node, the configuredtime resources to the donor node; or

detecting, by the relay node, a SSB transmitted by a surrounding nodebased on a hop count of the relay node, configuring, by the relay node,the time resources for itself based on a detection result, andreporting, by the relay node, the configured time resources to the donornode.

(16) The electronic device according to (12), wherein the node comprisesa donor node and a relay node, and the multiplexing manner comprises:

in a case that a link quality of a backhaul link of the relay node islower than a predetermined threshold, adjusting at least a part of thetime resources for the transmission of the SSB to be used for receptionfor the SSB.

(17) The electronic device according to (16), wherein the predeterminedthreshold is configured by the donor node for the relay node.

(18) The electronic device according to (16), wherein the multiplexingmanner further comprises:

in a case that at least the part of the time resources is adjusted to beused for reception for the SSB, adjusting, for an adjacent node of therelay node, corresponding time-frequency resources to be used fortransmission for the SSB.

(19) The electronic device according to (16), wherein the adjusting isperformed in the following manner:

transmitting, in a case that the link quality of the backhaul link ofthe relay node is lower than the predetermined threshold, a request tothe donor node by the relay node; and

configuring, by the donor node, more time resources for reception of theSSB for the relay node based on the request.

(20) The electronic device according to (1), wherein the referencesignal comprises Synchronization Signal Block SSBs, and

the configuration information comprises a manner of transmitting a SSBfor an access link and a SSB for a backhaul link by an adjacent node.

(21) The electronic device according to (20), wherein the mannercomprises:

transmitting, by the adjacent node, the SSB for the access link and theSSB for the backhaul link through orthogonal time resources; or

transmitting, by the adjacent node, the SSB for the backhaul link usinga directional beam.

(22) The electronic device according to any one of (1) to (21), whereinthe node comprises a donor node and a relay node, and the processingcircuitry is further configured to:

acquire hop count information indicating a relay hop count of the relaynode from the donor node.

(23) The electronic device according to (22), wherein acquiring the hopcount comprises:

determining a relay hop count of a relay node which transmits thereference signal, based on a predetermined correspondence between aresource position of the reference signal and the relay hop count,

wherein the reference signal comprises a Synchronization Signal BlockSSB, a Channel State Information Reference Signal CSI-RS or a systeminformation block signal, and

wherein the predetermined correspondence is notified by the donor nodeto the relay node.

(24) The electronic device according to (22), wherein acquiring the hopcount comprises:

acquiring the hop count information from a master system informationblock, radio resource control signaling or the reference signaltransmitted by a node.

(25) The electronic device according to (22), wherein the processingcircuitry is further configured to perform reselection of a backhaullink based on the following conditions:

hop counts of a current connection node and a candidate connection code;and/or

link qualities of a current connection node and a candidate connectionnode.

(26) The electronic device according to (25), wherein the reselection isperformed in the following manner:

determining, in a case that the condition of the candidate connectionnode is better than the condition of the current connection node, toswitch to the candidate connection node;

selecting a candidate connection node to be switched to, based on theconditions of a plurality of candidate connection nodes measured in agiven time window; or

reporting the conditions of the plurality of candidate connection nodesmeasured in a given time window to the donor node, and selecting, by thedonor node, a candidate connection node to be switched to.

(27) The electronic device according to any one of (1) to (21), whereinthe processing circuitry is further configured to:

determine, based on a time offset between signals of different nodesconnected via a backhaul link, an adjustment of synchronization time forat least one node of the different nodes.

(28) The electronic device according to (27), wherein the adjustmentcomprises:

adjusting, in a case that an offset between a Synchronization SignalBlock SSB for a superior node and a Synchronization Signal Block SSB fora subordinate node which are connected via a backhaul link exceeds apredetermined threshold, synchronization time for the subordinate node.

(29) The electronic device according to (28), wherein the processingcircuitry is further configured to:

in a case that the offset between the SSB for the superior node and theSSB for the subordinate node is greater than a predetermined upperlimit, determine, for the subordinate node, the configurationinformation as reducing a monitoring period for the SSB or increasingmonitoring positions for the SSB; and/or

in a case that the offset between the SSB for the superior node and theSSB for the subordinate node is lower than a predetermined lower limit,determine, for the subordinate node, the configuration information asincreasing a monitoring period for the SSB or reducing monitor positionsfor the SSB.

(30) The electronic device according to (27), wherein the adjustmentcomprises:

adjusting, in a case that an offset between a Synchronization SignalBlock SSB from a first node and a Synchronization Signal Block SSB froma third node which are received by a second node exceeds a predeterminedthreshold, synchronization time for the third node, wherein the firstnode, the second node and the third node are connected via a backhaullink, the first node is a superior node for the second node, and thesecond node is a superior node for the third node.

(31) The electronic device according to (27), wherein the adjustment isdetermined in the following manner:

transmitting, by a first node, timing configuration to a second nodeconnected with the first node via a backhaul link;

transmitting, by the second node, a synchronization maintenance signalto the first node based on the timing configuration; and

determining, by the first node, an adjustment of synchronization timefor the first node or the second node based on the timing configurationand a timing for the synchronization maintenance signal.

(32) A wireless communication method, comprising:

transmitting or receiving configuration information related toconfiguration of a reference signal for a discovery process of anIntegrated Access and Backhaul link IAB node.

(33) An electronic device for wireless communication, comprisingprocessing circuitry configured to:

acquire hop count information indicating a relay hop count of a relaynode from a donor node,

wherein the donor node is an Integrated Access and Backhaul link IABnode which is in wired connection with a core network, and the relaynode is an Integrated Access and Backhaul link IAB node which is not inwired connection with the core network.

(34) The electronic device according to (33), wherein acquiring the hopcount information comprises:

determining a hop count of a relay node that transmits a SynchronizationSignal Block SSB based on a predetermined correspondence between a timeresource position of the SSB and a relay hop count.

(35) The electronic device according to (33), wherein acquiring the hopcount information comprises:

acquiring the hop count information from a master system informationblock, radio resource control signaling or a reference signal for adiscovery process of an Integrated Access and Backhaul link IAB nodetransmitted by the relay node.

(36) The electronic device according to (33), wherein the processingcircuitry is further configured to perform reselection of a backhaullink based on the following conditions:

hop counts of a current connection node and a candidate connection code;and/or

link qualities of a current connection node and a candidate connectionnode.

(37) The electronic device according to (36), wherein the reselection isperformed in the following manner:

determining, in a case that the condition of the candidate connectionnode is better than the condition of the current connection node, toswitch to the candidate connection node;

selecting a candidate connection node to be switched to, based on theconditions of a plurality of candidate connection nodes measured in agiven time window; or

reporting the conditions of the plurality of candidate connection nodesmeasured in a given time window to the donor node, and selecting, by thedonor node, a candidate connection node to be switched to.

(38) A wireless communication method, comprising:

acquiring hop count information indicating a relay hop count of a relaynode from a donor node,

wherein the donor node is an Integrated Access and Backhaul link IABnode which is in wired connection with a core network, and the relaynode is an Integrated Access and Backhaul link IAB node which is not inwired connection with the core network.

(39) An electronic device for wireless communication, comprisingprocessing circuitry configured to:

determine, based on a time offset between signals of different nodesconnected via a backhaul link, an adjustment of synchronization time forat least one node of the different nodes.

(40) The electronic device according to (39), wherein the adjustmentcomprises:

adjusting, in a case that an offset between a Synchronization SignalBlock SSB for a superior node and a Synchronization Signal Block SSB fora subordinate node which are connected via a backhaul link exceeds apredetermined threshold, synchronization time for the subordinate node.

(41) The electronic device according to (40), wherein the processingcircuitry is further configured to:

in a case that the offset between the SSB for the superior node and theSSB for the subordinate node is greater than a predetermined upperlimit, cause the subordinate node to reduce a monitoring period for theSSB or increase monitoring positions for the SSB; and/or

in a case that the offset between the SSB for the superior node and theSSB for the subordinate node is lower than a predetermined lower limit,cause the subordinate node to increase a monitoring period for the SSBor reduce monitoring positions for the SSB.

(42) The electronic device according to (39), wherein the adjustmentcomprises:

adjusting, in a case that an offset between a Synchronization SignalBlock SSB from a first node and a Synchronization Signal Block SSB froma third node which are received by a second node is greater than apredetermined threshold, synchronization time for the third node,wherein the first node, the second node and the third node are connectedvia a backhaul link, the first node is a superior node for the secondnode, and the second node is a superior node for the third node; and/or

adjusting, by the second node, a transition gap between an uplink and adownlink based on the offset, wherein the transition gap is configuredby a donor node or by a superior node for the second node.

(43) The electronic device according to (39), wherein the adjustment isdetermined in the following manner:

transmitting, by a first node, timing configuration to a second nodeconnected with the first node via a backhaul link;

transmitting, by the second node, a synchronization maintenance signalto the first node based on the timing configuration;

determining, by the first node, an adjustment of synchronization timefor the first node or the second node based on the timing configurationand a timing for the synchronization maintenance signal.

(44) A wireless communication method, comprising:

determining, based on a time offset between signals of different nodesconnected via a backhaul link, an adjustment of synchronization time forat least one node of the different nodes.

(45) A computer readable medium comprising executable instructions that,when executed by an information processing apparatus, cause theinformation processing apparatus to implement the method according toany one of (32), (38) and (44).

1. An electronic device of an Integrated Access Backhaul (IAB) node forwireless communication, comprising circuitry configured to: listen to asynchronization signal from a parent IAB node of the IAB node to obtaina timing of the parent IAB node, receive a timing configuration from theparent IAB node for a time-domain synchronization across multiplebackhaul hops, perform a timing adjustment based on the timingconfiguration and a timing of the parent IAB node, and transmit a signalbased on the timing adjustment, wherein the IAB node connects to theparent IAB node via a wireless backhaul link.
 2. The electronic deviceaccording to claim 1, wherein the circuitry is configured to generate atiming configuration for a child IAB node of the IAB node to enable atime-domain synchronization of the child IAB node to the IAB node. 3.The electronic device according to claim 2, wherein the timingconfiguration for the child IAB node is related to a timer in theelectronic device, and the time-domain synchronization of the child IABnode to the IAB node is conducted by the electronic device according tothe timer.
 4. The electronic device according to claim 2, wherein thecircuitry is configured to transmit the timing configuration for thechild IAB node to the child IAB node.
 5. The electronic device accordingto claim 4, wherein the circuitry is configured to: receive asynchronization maintenance signal from the child IAB node based on thetiming configuration for the child IAB node, stop the timer, andcalculate a duration of the timer, determine whether an offset valuebetween the duration and a previous duration value is greater than athreshold, and based on the offset value being greater than thethreshold, generate and transmit a timing adjustment of the timingconfiguration for the child IAB node.
 6. The electronic device accordingto claim 5, wherein the timing configuration for the child IAB nodecomprises a bit string indicating time-frequency resources and a periodfor transmitting the synchronization maintenance signal from the childIAB node.
 7. A method performed by an electronic device of an IntegratedAccess Backhaul (IAB) node for wireless communication, the methodcomprising: listening to a synchronization signal from a parent IAB nodeof the IAB node to obtain a timing of the parent IAB node, receiving atiming configuration from the parent IAB node for a time-domainsynchronization across multiple backhaul hops, performing a timingadjustment based on the timing configuration and a timing of the parentIAB node, and transmit a signal based on the timing adjustment, whereinthe IAB node connects to the parent IAB node via a wireless backhaullink.
 8. The method according to claim 7, further comprising: generatinga timing configuration for a child IAB node of the IAB node to enable atime-domain synchronization of the child IAB node to the IAB node. 9.The method according to claim 8, wherein the timing configuration forthe child IAB node is related to a timer in the electronic device, andthe time-domain synchronization of the child IAB node to the IAB node isconducted by the electronic device according to the timer.
 10. Themethod according to claim 8, further comprising: transmitting the timingconfiguration for the child IAB node to the child IAB node.
 11. Themethod according to claim 10, further comprising: receiving asynchronization maintenance signal from the child IAB node based on thetiming configuration for the child IAB node, stopping the timer, andcalculating a duration of the timer, determining whether an offset valuebetween the duration and a previous duration value is greater than athreshold, and based on the offset value being greater than thethreshold, generating and transmitting a timing adjustment of the timingconfiguration for the child IAB node.
 12. The method according to claim11, wherein the timing configuration for the child IAB node comprises abit string indicating time-frequency resources and a period fortransmitting the synchronization maintenance signal from the child IABnode.
 13. A non-transitory computer readable product containinginstructions to cause an electronic device of an Integrated AccessBackhaul (IAB) node for wireless communication to perform a method, themethod comprising: listening to a synchronization signal from a parentIAB node of the IAB node to obtain a timing of the parent IAB node,receiving a timing configuration from the parent IAB node for atime-domain synchronization across multiple backhaul hops, performing atiming adjustment based on the timing configuration and a timing of theparent IAB node, and transmit a signal based on the timing adjustment,wherein the IAB node connects to the parent IAB node via a wirelessbackhaul link.